In electronics industries, circuit board manufacturers are responsible for the production of multi-layer circuit boards, while assembly companies are responsible for wire bonding and packaging the chips on the multi-layer circuit boards and for electrical properties tests of the electronic components after the chips and the circuit boards are packaged to be electronic components in the packaging procedures.
Before the chips and the conventional multi-layer circuit boards are delivering to the assembly company, electrical properties tests can be applied to the chips but cannot be applied to the conventional multi-layer circuit board. As a result, after the packaging procedures, the multi-layer circuit board, units on the multi-layer circuit board, and connections between the multi-layer circuit board and the units have to be checked and analyzed carefully to find problems when the electrical properties tests of the component are not qualified. Nevertheless, the sizes of such kinds of electronic components are quite tiny and the structures of the electronic components are fine. As a result, it takes time and labor to find out the reasons causing the unqualified electrical testing result. Furthermore, the responsibilities for the unqualified electrical testing result cannot be clarified.